Cognitive theory of worldview in language specifies speakers’ ability to isolate a prototype as the construct of interpretative reality and to use a stereotype as an associative prototype, a process undertaken by certain Slavic cultures. Linguistic conceptualization of basic color categories provides data to explore criteria for assigning prototypes as well as the reasons to encode stereotypes. Data derive from nineteenth century Russian, Ukrainian, and Serbian folklore. Therein, color prototypes are radiant and positive, nonprototypes not radiant and secondary, for which they come to symbolize negative stereotypes. Each color concept harbors a duality of both semantic potentials, which appear to descend from like oppositions in ancient ancestral languages. The data provide background in time depth for comparison with outcomes of associative experiments and with results from psycholinguistic research in contemporary Russian and Ukrainian.